Process and apparatus for removal of asbestos floor tile

ABSTRACT

A method for removal of asbestos floor tile comprising the following steps: lowering the temperature of a selected tile section and the adhesive material between said tile(s) and the juxtaposed subflooring; maintaining the temperature reducing agent for a period of time sufficient to cause said adhesive material/layer to substantially lose its bonding properties; removing the de-bonded asbestos tile from the subflooring and disposing according to Governmental regulations. 
     A manually transportable housing dimensioned for receiving therewithin a quantity or block of dry ice. Said housing having a bottom section defining an opening for being aligned with a selected asbestos floor tile(s). Blower means mounted to said housing for directing an air stream over said dry ice and downwardly through said opening unto said tile(s).

FIELD OF THE INVENTION

The present invention is directed to a method and apparatus for removalof floor tile, and in particular the relatively safe removal of asbestosfloor tile.

BACKGROUND OF THE INVENTION

It is often necessary to remove and replace asbestos floor tile withnon-asbestos tile. Typically, the asbestos tile is manually removed byscraping and breaking sections of the tile with a knife and other bladedevices, which can cause dangerous asbestos particles to becomeairborne. Simply forcing or breaking off the asbestos tile by mechanicalmeans is laborious, relatively expensive, inefficient and hazardous tothe workers and others within the general environment. In addition, theproblem of containing/stacking, shipping and disposing of the hazardousscraps and pieces of waste material produced by the prior art methods issubstantial. It is noted that such prior art methods produces numerousasbestos fiber surfaces about each broken-off piece of tile and,consequently, detectable airborne asbestos contamination of the airenvironment.

Since large quantities of scraps and pieces of tile are more difficultto containerize, transport, and store than uniform originally shapedtile sections, for example, flat square foot tiles, such prior arttechniques and removal methods are relatively expensive and wasteful ofour limited disposal sites for hazardous materials.

BRIEF DESCRIPTION OF FOUR RELATED PRIOR ART PATENTS

1. U.S. Pat. No. 3,934,379 issued Jan. 27, 1976, to Norman R. Braton andJan R. Acker, describes a method for removal of layers of organicmaterial built up on a support for articles during surface coating.

This patent does not teach the use of cryogens or any other temperaturelowering method for the removal of hazardous asbestos floor tile, nor isthis patent concerned with and does not recognize the problems ofremoval, handling, transporting and storing of hazardous asbestosmaterials.

2. U.S. Pat. No. 4,956,042 issued Sep. 11, 1990, to Jean-Luc Hubert, etal, describes a method of embrittling and removing an outer protectivecoating of a pipe or pipeline. The pipe is enclosed to define an annularspace and a cryogen is expanded within this annular space to causeembrittlement of the coating to be removed.

Thus, it is an object of this patented invention to embrittle thecoating material, i.e., the protective coating surrounding a pipe, tofacilitate its removal. This patented invention does not appear to beconcerned with nor does it teach a method to substantially reduce and/oreliminate the causes of airborne asbestos that may result from thebreaking of embrittled floor tile sections.

In total contrast to the '042 patent discussed above, the presentinvention is directed not at the embrittlement of asbestos floor tilebut rather the freeing or debonding of the floor tiles from thesubflooring in substantially unbroken condition with its structuralcharacteristics and asbestos fibers within the tile substantiallyunchanged from its condition prior to removal. In this manner, it is anobject of the present invention to enable removal of intact floor tileswith their structural integrity substantially maintained, i.e., itsproperties to constrain the asbestos fibers unchanged.

3. U.S. Pat. No. 2,421,753 issued Jun. 10, 1947 to W. J. Joyce teaches ameans for unblocking lenses. This patent does not show, describe, orsuggest a method for removing floor tile while substantially reducing oreliminating the risk of causing the release of airborne asbestos fibersinto the environment.

4. U.S. Pat. No. 2,399,679 issued May 7, 1946 to G. W. Jackson alsoshows a means for unblocking lenses. It is noted that this patent is notconcerned with nor does it suggest or describe a method of handlinghazardous waste materials such as asbestos.

SOME OF THE ADVANTAGES OF THE PRESENT INVENTION

In total contrast with the prior art patents noted above and the priorart related to the removal of floor tiles, the present inventionprovides a more efficient, cost effective and substantially safer methodand means for the removal of floor tiles, and in particular, floor tileswhich contain hazardous materials and fibers, such as asbestos. Anotheradvantage of the present invention resides in the relative ease and lessexpensive handling of the removed tile which can be readily stacked incontainers and shipped for safe disposal. Also, since the tiles areremoved in one piece, i.e., the sections as installed which aretypically one foot squares by approximately one eighth inch thick,substantially less asbestos fiber exposed ragged edges are exposed tothe air and the workers doing the removal, stacking, shipping anddisposal work.

OBJECTIVES OF THE INVENTION

It is an object of the present invention to provide an improved methodfor the removal floor of tile.

It is a further object of the present invention to provide a new methodfor the removal of asbestos floor tile.

It is a further object of the present invention to provide a new methodfor preventing the release of asbestos fibers into the air whileremoving asbestos floor tile from subflooring.

It is a further object of the present invention to provide a new methodfor the removal of asbestos floor tiles whereby each tile may be removedintact.

It is a further object of the present invention to provide a method forpreventing asbestos fibers from becoming airborne during the removal ofasbestos containing tile from floors.

It is a further object of the present invention to provide a method ofreplacing floor tiles.

It is a further object of the present invention to provide a method ofremoving asbestos floor tile whereby broken tile edges are eliminated.

It is a further object of the present invention to provide a method forthe removal of floor tile whereby the removed tile may be stacked forrelatively inexpensive transportation.

It is a further object of the present invention to provide a method forthe removal of asbestos containing floor tile from a subfloor withoutbreaking or cracking the tile into pieces.

It is a further object of the present invention to provide a new methodfor debonding a floor tile from a supporting structure.

It is a further object of the present invention to provide a method forrendering the bonding and/or adhesive medium between a tile and asupporting surface ineffective as a bonding medium whereby the tile maybe readily removed.

It is a further object of the present invention to provide a new andimproved method of altering the bonding and/or adhesive quality of thebonding agent between a floor tile and the subfloor supporting said tilewhereby the floor tile may be more quickly and easily removed.

It is a further object of the present invention to provide a moreeconomical method for the removal of floor tile.

It is a further object of the present invention to provide asubstantially less laborious method and system for the removal of floortile.

It is a further object of the present invention to provide a new andimproved method and system for removing and handling hazardous wastematerial asbestos floor tiles.

It is a further object of the present invention to provide a new meanswhereby asbestos floor tile may be relatively more economically, easilyand safely removed.

It is a further object of the present invention to provide a new andimproved means whereby removed asbestos floor tile can be relativelymore economically, easily and safely stacked, containerized andtransported for disposal.

Further and other objects of the invention may be and may becomeapparent to one skilled in the art by a perusal of the disclosure in thepresent application, and it is to be understood that the presentshowings are by way of illustration only and are not to be considered aslimitations.

SUMMARY OF THE INVENTION

Dry ice is placed in a frame mounted on wheels. The dry ice is coveredwith, for example, wet burlap, which dry ice rests on the (asbestos)floor tiles. Electric fans mounted on the frame blow air over thecovered dry ice, down onto the asbestos floor tiles. The gases createdby this procedure, (dry ice turns to gas at 78.5c/110F) cause thecomplete and clean separation of the (asbestos) floor tile from thesubflooring.

When this process is monitored by approved Federal and State airmonitoring equipment, a zero contaminant reading has been observed.

An asbestos floor tile removal system for uplifting asbestos floor tilefrom a subfloor, comprising:

means for reducing the temperature of the asbestos floor tile for aperiod of time to effect a substantial debonding between the asbestostile and the underlying subfloor;

means for uplifting the debonded asbestos tile off the subfloor;

whereby the debonded and uplifted asbestos tile being removedsubstantially without degradation and virtually without emission ofasbestos into the surrounding environment.

A relatively safe method for the removal and containerization ofobsolete floor tile previously adhered to a subfloor by a bonding agent,which floor tile contains one or more hazardous materials such asasbestos, comprising the steps of:

applying a temperature reducing agent such as dry ice or a cryogen toone or more selected floor tile for a selected period of time forcausing a reduction of the temperature of the selected floor tile andthe underlying bonding agent to a level whereby the bonding agent beingrendered substantially ineffective as a bonding medium;

uplifting the debonded floor tile in substantially uniform and unbrokenfloor tile sections;

stacking the uplifted uniform floor tile sections into container means;

sealing said container means for shipment;

whereby the debonded floor tile may be removed and containerized withvirtually a zero hazardous material air contamination risk to theworkers.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 is a perspective view of embodying apparatus designed inaccordance with the present invention and being shown in operationaldisposition on a tile floor;

FIG. 2 is a perspective view of the apparatus shown in FIG. 1, with thetop cover means and blower removed;

FIG. 3 is a top diagramatic view of the apparatus shown in FIG. 1, withthe top cover means and blower removed;

FIG. 4 is a perspective view of an alternative embodiment of apparatusdesigned in accordance with the present invention;

FIG. 5 is an exploded view of the alternative embodiment of apparatusillustrated in FIG. 4;

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment and an alternative embodiment of the inventionwill now be described with reference to the attached drawings, in whichthe same reference numerals are used to represent the same orcorresponding elements throughout the various views.

With particular reference to FIGS. 1, 2, and 3, the apparatus 10 of theinvention has a main housing 11, which is formed of a rigid materialsuch as wood, plastic or metal. The housing 11 is basically formed oftwo side board members 12, 13 having a length of approximately 72inches, a height of approximately 9 inches and a thickness ofapproximately 3/4 inch, and two end board members 14, 15 each having alength of approximately 36 inches, height of approximately 9 inches anda thickness of approximately 3/4 inch. Although the housing 11 has arectangular configuration in accordance with the preferred embodiment ofthe invention, other shapes such as a square may be utilized in whichthe side and end board members are of substantially equal dimensions.Lateral support beams 16 may be structurally affixed to the housing 11in conventional manner, for example, with screws, nuts and bolts (notshown) to provide increased structural strength and integrity to housing11.

Four rollers or casters 17 of conventional design are operativelymounted to housing 11 in conventional manner, for example, by means ofscrews (not shown), nuts and bolts and mounting brackets 18, tofacilitate the ability of a worker/operator to move and deploy theinventive device or apparatus 10 on and about a tile floor 19. Eachcaster 17 is set within a respective alcove 20 of housing 11 to enablethe inventive device 10 to be placed in close juxtaposition with thewalls (not shown) of the building. In this manner, application to ortreatment of the tiles close to such walls may be accomplished. Eachcaster 17 is recessed within the respective alcoves 20 whereby thehousing 11 is held slightly above the tile floor 19 a predetermineddistance. For example, the bottom edges 21 of the side and end members12-15, are maintained approximately 1/8 to 3/4 inches above the floortile 19.

A top cover 22 having peripheral dimensions substantially equal to thedimensions of housing 11 is provided atop housing 11. Top cover 22 maybe formed of burlap or other suitable material to cover the upperopenings 23 formed within housing 11.

A blower device 25 is placed or mounted atop cover member 22 and issupportably positioned over support beams 16. Blower device 25 may be ofconventional design having one or more electrically powered fans (notshown) for directing a stream of air downwardly over portions of acoolant such as dry ice and thence unto the floor tile.

OPERATION OF THE PREFERRED EMBODIMENT

The operation of the preferred embodiment of the invention will now bediscussed with reference to FIGS. 1-4.

The housing 11 is placed on the tile floor selected for removal.

The interior spaces or alcove(s) 23 of housing 11 are substantiallyfilled with dry ice 26.

Top cover 22, consisting of wet burlap, is placed over the dry ice 26 tosubstantially contain the gases being formed and the lower temperaturescaused by the evaporating dry ice from freely escaping upwardly into theroom environment.

The blower device 25, having one or more fans, is placed atop the burlapcover 22 and energized, via plug 24, to cause, a continuous flow of airthrough the wet burlap across the surface areas of the dry ice 26 anddownwardly unto the tile floor beneath apparatus or debonder 10.

Debonder 10 is maintained in position over selected tile sections for aperiod of time sufficient to cause the bonding agent or cement glue 27to substantially or completely lose its bonding or gluing propertiesbetween the treated tile and the underlying subfloor 28. The minimumtime period may be determined empirically so as to enable an efficientand economical and quick debonding process.

Following the debonding process, debonder 10 is disposed over anotherselected portion of the tile floor 19 and the debonding processcontinues in a progressive section-by-section manner until all the tilesselected for removal have been debonded.

Following each sectional debonding, the debonded tiles, for example,tile 29 may be manually uplifted by a worker 30 (partially shown) withrelative ease using standard tools 31, with the tiles 29, beinggenerally intact. Since each tile is similarly removed intact, virtuallyno asbestos or other undesired and/or hazardous dust, and fibers areemitted into the rooms air environment. IN addition, since the tiles 29,are not broken into numerous ragged smaller pieces which are relativelymore hazardous to handle, the workers are at less risk from lung, skinand clothing exposure and, consequently, contamination from asbestos.Thus, not only are the workers' risks reduced but also the risk isreduced for the family members who may come into contact with hisclothing.

Next, the worker 30 (partially shown) can stack the substantiallyuniform (generally square) tiles into relatively neat piles 32 forremoval from the work site or directly into cartons 33.

As each stack 32 of tiles is containerized, the neatly packaged tile maybe more economically transported to a government approved disposal site.It should now be appreciated that not only are the risks of asbestosfiber contamination at the floor tile uplifting and containerizing sitereduced or virtually eliminated, but that the risk to thetransporters-carriers is also substantially reduced. For example, itshould be apparent that much less risk of asbestos contamination islikely to occur if a carton of intact tiles should rupture or open whilein transit than if the transporting container was filled with numerousvarious sized and shaped bits and pieces of ragged edged asbestos tile.

DESCRIPTION OF ALTERNATIVE EMBODIMENT

With reference now to FIGS. 4 and 5, an alternative embodiment 39 of theinvention apparatus and system will now be discussed.

Housing frame 34 basically comprises a rectangular shaped frame havingelongated side walls 35, 36, front end wall member 37, and rear end wallmember 38. A pair of front and rear rollers or casters or roller bearingmeans 40 are mounted in conventional manner to housing 34.Roller-bearings 40 are mounted to facilitate the disposition of debonder39 upon the tile floor 19, and to space the bottom edges 41 of housing34 slightly higher, for example, between 1/8 inch to 1 inch, above thetile floor 19.

A skirt member 42 is affixed by conventional means, such as screws 43,about the lower periphery of housing 34. Skirt member 42 may be formedof rubber, plastic or other suitable material and a plurality ofprotruding fibers 44 similar to a brush or other suitable substances toform a flexible skirt means which extends downwardly into rubbingcontact with the tile floor 19. The general purpose of the skirt member42 is to form a flexible element with the contours of the tile floor 19,while constraining the refrigerant reduced temperature in contact withthe tiles located below debonder 39.

A cover plate 45 is provided to be mounted to frame 34, for example, byhinge means 46. Cover plate 45 is dimensioned to rest upon theperipheral ledge or edge 47 of frame 34. Cover plate 45 is affixed toframe 34 in conventional manner, for example, by screws and hinges 46.Cover plate 45 may be formed of metal, wood, plastic or other suitablematerial. A plurality of holes 48 are provided in cover plate 45 toaccommodate nozzle means 49 discussed in more detail hereinafter.

Pipe network 50 is mounted atop cover plate 45. Pipe network 50comprises a refrigerant or cryogen distribution means. Pipe network 50may be formed of metal or plastic pipes having suitable properties as aconduit for the cryogen-refrigerant to nozzle means 49. Pipe network 50is operatively connected to a source 51 of pressurized refrigerant orliquid cryogen such as, for example, liquid nitrogen or carbon dioxide.A control valve 52 is connected to pipe network 50 for controlling theflow rate of the refrigerant/cryogen to nozzle means 49.

Nozzle means 49 comprises a plurality of conventional nozzlesoperatively connected to pipe network 50 for applying or distributingthe refrigerant/cryogen substances downwardly into chamber 53 which isdefined by frame 34 and cover plate 45. Gasket means (not shown) may beprovided as a seal between cover plate 45 and nozzle means 49.

A handle means 55 may be provided to facilitate placement and handlingof debonder 39. A temperature gauge means 56 of conventional design maybe operatively mounted to debonded 39 having a temperature measuringmeans 60 projection via hole 61 into the refrigeration chamber 53.

A mounting rack 57 comprises a plurality of bars 58 affixed, forexample, welded 59, to cover plate 45 to form a container 33 receivingstorage rack means.

OPERATION OF THE ALTERNATIVE EMBODIMENT

The operation of the alternative embodiment of the invention will now bediscussed.

The debonder 39 is placed on the tile floor 19 with skirt means 42contributing to form a substantial cooling chamber 53.

Control valve 52 is opened to permit the flow of the refrigerant/cryogenliquid/gas to flow through pipe network 50 and delivered, via nozzlemeans 49, into the cooling chamber 53. In this manner, the loweredtemperature within chamber 53 is applied to the floor tiles positionedbelow chamber 53 and, thereby, to the bonding agent 27. Thus, in similarmanner to the preferred embodiment, the bonding agent 27 is subjected tosuch lowered temperature for a period of time to cause the debondingeffect. This time period may be empirically determined.

The other process steps and system is similar to that describe abovewith reference to the preferred embodiment.

Obviously, numerous modifications and variations of the presentinvention are possible in light of the above teachings. It is thereforeto be understood that within the scope of the appended claims, theinvention may be practiced otherwise that as specifically describedherein.

In the appended claims the terms "debond" or "debonding" are used todefine a process whereby air, gas, cryogen refrigerant agent or dry ice(having a relative low temperature) is applied to a floor tile to causethe substantial or total ineffectiveness of the bonding agent to bond orhold in place such tiles with the subfloor.

The term "Debonder" is used to describe apparatus designed in accordancewith the present invention to apply or implement one or more steps inthe debonding containerizing process of floor tiles.

What is claimed is:
 1. A relatively safe method for the removal andcontainerization of obsolete floor tile previously adhered to a subfloorby a bonding agent, which floor tile contains one or more hazardousmaterials, comprising the steps of:applying a temperature reducing agentselected from the group consisting of dry ice and a cryogen to one ormore selected floor tiles for a selected period of time for causing areduction of the temperature of the selected floor tile and theunderlying bonding agent to a level whereby the bonding agent isrendered substantially ineffective as a bonding medium; uplifting thedebonded floor tile in substantially uniform and unbroken floor tilesections; stacking the uplifted uniform floor tile sections intocontainer means; sealing said container means for shipment; whereby thedebonded floor tile may be removed and containerized with virtually azero hazardous material air contamination risk to the workers.